In the U.S., "it's not as panicky as others make it out to be," Overduin said. "I can say the supply is very, very tight. Last year we were just a little bit short of what we wanted, and this coming year, it looks like we'll have sufficient availability. We won't know that for sure for at least another two months."

Since 2007, the amount of kale grown in the U.S. has risen by 57 percent as its health-conscious reputation and trend-loving consumers have driven sales of the leafy vegetable.

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Chris Ronis, co-owner of Northern Spy Food Co., a New York City restaurant, called the green a "cornerstone" of its menu. Kale salad ranked as the establishment's most popular item, outselling the next best-selling dish by 5 to 1 and garnering press with Eater and The New York Times.

While Ronis doesn't think his restaurant's kale supply would be affected by a seed scare, he is somewhat worried about prices.

"We source most of our produce from little and small farms, most of which would not be purchasing their seeds from a large company, I would think, so it wouldn't affect us, I'd hope," he said. "If there is a shortage at an industrial level, it still will affect our prices because people will start seeking out smaller farms and other sources."